The present invention relates to the field of personal alarms and, more particularly, to a personal alarm apparatus intended to aid against accidental drowning, including a method for an operator to monitor the whereabouts of a subject in or out of the water.
The present invention provides a personal monitoring apparatus useful in helping prevent accidental drownings, particularly with children, the elderly, and handicapped subjects. Additionally, the apparatus is useful for monitoring separation distance, thus helping prevent a monitored subject from wandering away from a supervising operator. Similar systems including compact, portable monitoring units have been previously described and are known in the art. However, no previous system incorporates all the features and advantages of the present invention. The present invention provides water-activated warning systems, a distance warning, a manually activated warning, directional finding capability, and the ability for one base station to individually monitor multiple remote stations. This last function being particularly useful in group situations, such as summer camps, daycares, nursery schools, elder care, and others.
With the foregoing in mind, the present invention advantageously provides a personal monitoring apparatus and method for an operator to monitor the whereabouts of a subject. The apparatus includes one or more portable remote units and a base unit. The portable remote unit is connected to the subject to be monitored and includes a remote unit power supply, a radio transmitter for sending a remote unit radio signal, a radio receiver for receiving a base unit radio signal, remote unit alarm having a light activated water sensor, and a dye pack for releasing dye substantially responsive to submersion of the remote unit in water. The remote unit may include a power switch positioned such as to substantially prevent the remote unit from being turned off by the subject. The apparatus also includes a portable base unit in radio communication with the remote unit for enabling the operator to monitor the whereabouts of the remote unit, and thereby also the whereabouts of the subject. The base unit includes a base unit power supply, a radio transmitter for sending the base unit radio signal, a radio receiver for receiving the remote unit radio signal, a distance estimating function for substantially estimating the distance between the base unit and the remote unit, a base unit alarm responsive to the remote unit radio signal, and a direction finding function for generally finding the direction from which the remote unit signal originates. Both the base unit and the remote unit may be housed in an accessory or a garment. For example, the base unit may be housed in an accessory such as a wrist band to be worn by the operator performing the monitoring. The remote unit may be housed in a garment, such as a shirt to be worn by the subject, perhaps a child. The apparatus incorporates an alarm activated by excessive distance between the remote unit and the base unit or by the remote unit being submerged in water. An alarm on the remote unit may also be activated manually from the base unit at the operator""s discretion.